Manual and automatic switch with handle lock and indicator



NOV. 29, 1966 y E` T, PLATZ ET AL 3,288,966

MANUAL AND AUTOMATIC SWITCH WITH HANDLE LOCK AND INDICATOR K Filed Deo. 7, 1965 5 Sheets-Sheet 1 N LQ' @HFR Nov. 29, 1966 E. T. PLATZ ET AL MANUAL AND AUTOMATIC SWITCH WITH HANDLE LOCK AND INDICATOR 5 Sheets-Sheet 2 Filed Dec. '7, 1965 -mw .E

Nov. 29, 1966 E. T. PLATZ ET AL MANUAL AND AUTOMATIC swIIoH wIIH HANDLE LOCK AND INDICATOR 5 Sheets-Sheet ."5

Filed Dec. '7, 1965 INVENTORS Nov. 29, 1966 E. T. PLATZ ET AL MANUAL AND AUTOMATIC SWITCH WITH HANDLE LOCK AND INDICATOR 5 Sheets-Sheet 4 Filed Dec. 7, 1965 ...NL 0H .NIRI

mi @3M MMf 1MM @WP M -UNE Nov. 29, 1966 E. r. PLATZ ET AL n MANUAL AND AUTOMATIC SWITCH WITH HANDLE LOCK AND INDICATOR 5 Sheets-Sheet 5 Filed Deo. '7, 1965 United States Patent Olice Patented Nov. 29, 1966 3,288,966 MANUAL AND AUTMATIC SWITCH WITH HANDLE LQCK AND INDICATOR Elwood T. Platz, Grosse Pointe Farms, Bernard D Marco, Lincoln Park, and Albert F. Kendall, Detroit, Mich., assignors to I-T-E Circuit Breaker Company, Philadelphia, Pa., a corporation of Pennsylvania Filed Dec. 7, 1965. Ser. No. 512,152

9 Claims. (Cl. 200-116) This invention relates to electric switches in general and more particularly relates to manually and automatically operable switches for controlling lighting, small motors and other low and moderate power electric circuits.

` Manually and automatically operated switching devices, especially those intended to control the operation of small motors, are often adapted to be mounted in smallv metal wall boxes of standard dimensions. It is desirable that the dimensions of the switching device especially in the region of the line and load terminals be made as small as possible in order to increase the available wiring space within the wall box. Since switching devices for motor control are usually two pole units and are provided with readily `changeable heating elements of the automatic tripping means, the prior art has found it extremely difficult to construct sufliciently -compact switching devices of this type.

Accordingly, a primary object of the instant invention is to provide a novel manually and automatically operable switching device suitable for fractional horsepower motors, control circuitry and circuits of the same current ratings.

Anotherobject is to provide a switching device of this type having small height and depth dimensions for given .power ratings. Still another object is to provide a switching device of this type whi-ch may be used to controla wide range of Ielectrical loads by means of interchangeable heating elements which may be readily replaced yet are securely connected in the circuit.

A further object is to provide a switching device of this type which includes handle locking means as well as indicating means to show the electrical condition of the switching device.

These as well asvother objects of this invention will become readily apparent after reading the following de scription of the accompanying drawings in which:

FIGURE 1 is a front elevation of a switch constructed in accordance with the teachings of the instant invention.

FIGURES 2 through 4 are side elevations of the subassembly constituting the contact operating mechanism looking in the direction of arrows 6-6 of FIGURE l. In FIGURE 2 the elements of the subassembly are shown in the manually Off position of the switch, in FIGURE 3 these elements are shown in the On position of the switch and in FIGURE 4 these elements are shown in the tripped open position of the switch.

FIGURE 5 is an exploded perspective showing the v main electrical and oper-ating elements of the switch shown in FIGURE 1.

FIGURE 6 is a side elevation looking in the direction of arrows 6-6 of FIGURE l with portions of the housing broken away to reveal internal elements of the switch.

FIGURE 7 is a rear elevation looking into the rear or open end of the base.

FIGURE 8 is a cross section taken through line 8-8 of FIGURE 7 looking in the direction of arrows 8 8.

FIGURES 9 and 10 are partialv cross-sections taken through lines 9-9 and lil-J0, respectively, of FIGURE l looking in the directions of the respective arrows 9 9 and l0-10.

t FIGURE 11 is an end view of the locking bracket and cooperating elements looking in the direction of arrows 11-11 of FIGURE 1.

FIGURE l2 is anexploded perspective of the elements required to convert the switch of FIGURE 1 to a key operated device.

FIGURE 13 is a side elevation showing the elements of FIGURE 12 in assembled condition positioned for operation of the switch mechanism.

FIGURE 14 is an electrical schematic of the switch illustrated in FIGURE 1.

Now referring to the figures and more particularly to FIGURES 1 and 14. Switch 10 is atwo pole unit having a manual operating handle 11 for operating of bridging contacts 12 and 13. As will hereinafter be shown in greater detail, with switch 10 closed contact 12 bridges the gap between stationary contacts 14, 15 and contact 13 bridges the gap between stationary contacts 16, 17. Contact 14 is connected to load terminal 18, contact 15 is connected to line terminal 19, contact 16 is connected to line terminal 20 and contact 17 is connected to the female part 21 of plug-in connector 22. The male part 23 of connector 22 is connected to one end of heater 25 whose other end is connected to load terminal 24.

Neon indicator lamp 26 (FIGURE 14) is in series with current limiting resistor 26a with the series combination electrically connected to load terminals 18 and 24 by insulated conductors 18a and 24a, respectively.

The manually .engageable part 11a of handle 11 extends through aperture 27 in the front wall of the housing base 30. Handle 11 is pivotally mounted on pin 31 extending through aligned apertures 31a in the spaced walls of U-shaped frame 32. With respect to FIGURES 2 through 4, handle portion 11a extends to the left from xed pivot 31 through aperture 33 in the web of frame 32. Downward extension 11b of handle 11 extends between the spaced walls of frame 32 as well as between the spaced walls of mechanism actuator 34 and is provided with elongated slot 11:,` whose longitudinal axis extends through the center of pivot 31. Movable pivot pin 35, extending between the spaced walls of mechanism actuator 34, extends through` slot 11C.

Mechanism actuator 34 is pivotally mounted on stationary pin 36 extending through aligned apertures 36a in the spaced walls of frame 32. The spaced arms of mechanism actuator 34 are provided with aligned slots 37 which receive pivot projections 33 extending outwardly from the spaced arms of carrier actuator 40 near the free ends thereof to provide a pivotal connection between actuators 34 and 40. Coiled tension main spring 41 is connected at one of its ends 41a to the web of carrier actuator 40 while the other end 41h of spring 41 is connected to the hook-like formation at the free end 42 of cradle 43. Cradle 43 is a generally inverted T-shaped member positioned on its side as seen in FIGURES 2 through 4, with projection 42 corresponding to the T leg.

Pins 44, 45 are force fitted in apertures of cradle 43 extending on opposite sides of the plane of cradle 43 generally at right angles thereto. Pin 45 extends between the spaced arms of frame 32 and is received by aligned hook-like formation of frame 32 to pivotally mount cradle 43. Pin 44, as best seen in FIGURE 4, engages the spaced arms of frame 32 to limit clockwise movement of -cradle 43 about its pivot 45 when switch 10 is tripped open. Pivot pin 45 is at one end of the T cross arm while the other end 46 of the T cross arm extends to a notch at the right end of the -automatic tripping means bimetal 47 to latch cradle 43 in the reset position shown in FIGURES through aperture 43 near the center of insulating contact carrier sheet 50. Carrier 50 is provided with two additional apertures through which bridging contacts 12 and 13 extend with their respective contact pressure springs 49 disposed within these apertures.

Heater coil 25 is wound about insulating carrier sheet 53 extending in the same general direction as bimetal 47 and positioning heater coil 25 in close proximity to, but spaced from, bimetal 47 so that heat generated by current flowing through heater 25 will have a substantial heating effect upon bimetal 47. The latter, upon heating, will distort so that the right or free end thereof will deflect downward with respect to FIGURE 3 and upon predetermined overload conditions will deflect sufficiently to release cradle 43.

When handle 11 is operated manually in a clockwise direction from the Off position of FIGURE 2 to the On position of FIGURE 3 the pin slot connection 35, 11aI causes mechanism actuator 34 to pivot in a counterclockwise direction about fixed pivot 36 with movable pivot 38 being moved in a counterclockwise direction with respect to pivot 36 and passing through the line of action of spring 41 to a position to the left thereof. At the instant pivot 38 moves to the left of the line of action for spring 41, the latter is free to operate the web portion of carrier actuator 40 to the right or in a clockwise direction about pivot 38 moving contact carrier 50 to the right to operate bridging contacts 12 and 13 to closed position. Embossments 3211 on the confronting surfaces of the mechanism frame arms limit counterclockwise motion of mechanism actuator 34.

With switch in the On position of FIGURE 3, under predetermined overload conditions bimetal 47 will deflect downward sufficiently to release latch tip 46 of cradle 43. Main spring 41 is now free to pivot cradle 43 in a clockwise direction with respect to FIGURE 3 about its fixed pivot 45. One end 41h of spring 41 moves above pivot 38 and end 41a of spring 41 is free to operate carrier actuator 40 in a counterclockwise direction with respect to FIGURE 3 thereby moving contact carrier 50v leftward to its position shown in FIGURE 4 wherein bridging contacts 12 and 13 separate from their respective cooperating stationary contacts to open switch 10. Pin 44 engages frame 32 to limit clockwise movement of cradle 43 and in so doing limits the movements of actuators 34 and 40 so that handle 11 assumes a mid position indicating automatic trip.

As best seen in FIGURES 7 and 8, base 30 is a single molded member constructed of insulating material and is hollowed to form cavities which receive electrical and mechanical switch elements with the boundaries of such cavities positioning these switch elements. The rear of base 30 is open to permit the insertion of electrical and mechanical switch elements into base 30 through the rear thereof. Cover 61, shown phantomed in FIGURE 6, is a single member which mates with base 30 generally along line 62 and is secured to base 30 by screws (not shown) to close the rear of base 30 and thereby retain the electrical and mechanical switch elements in operative position within the housing formed by base 30 and its cover 61.

Base 30 is provided with a pair of confronting internal generally parallel walls 63, 63 having aligned parallel slots 64, 64 which receive the ends of pivot pins 31 and 36 to position frame 32 in base 30. In addition, frame 32 is positioned by the partially out-turned ears 32e received by notches 65, 65 in walls 63, 63. Hole 66 in base 30 receives the rivet 66a (FIGURE l) which secures mounting bracket 67 to base 30. Bracket 67 is provided with tapped hole 67a for attaching a face plate to switch 10 and clearance hole 67b for a screw which attaches switch 10 to a junction box. Hole 68 in base 30 is provided to receive a self tapping screw which secures the other bracket 69 to base 30. This latter bracket 69 is also provided with a tapped aperture for securement of the face plate and a clearance aperture to permit securement of switch 10 to a junction box.

The ends of contact carrier 50 are received by internal grooves 71, 71 of base 30 [as well as by grooves 72, 72 in the internal partitions 73, 73 of base 30 to journal the straight-line motion of contact carrier 50. Pocket 74 with lugs 75, 75 is provided in base 30 for the snapin reception of the lens 76 covering pilot light 26.

Base 30 is also provided with slots 77 divided into sections by barrier 78 to receive and position conducting strap 79 having stationary contact 17 at one end thereof and the female plug-in contact 21 at the other end thereof (see FIGURE 6). The upper heater terminal 24a is connected to an extension of load terminal 24 by means of screw 53a which is captively mounted to terminal 24a. The mounting of screw 53a to heater terminal 24a is such that when screw 53a is rotated to withdraw same from the threaded aperture in the extension of load terminal 24 adapted to receive same, heater carrier 53 and all of the elements mounted thereto move forward with heater plug-in terminal 23 partially withdrawing from its cooperating plug-in terminal 21.

Thus, it is seen that switch 10 is constructed with a one-piece base 30 and a single rear cover 61. The construction of switch 10 is such that the contact operating sub-assembly of FIGURES 2, 3 and 4 may readily be inserted into base 30 through the rear opening thereof with operating handle 11 projecting through base aperture 27.

Screws 199 extending through clearance apertures in one leg of locking bracket 201 are received by threaded apertures in base 30 to amount bracket 201 to base 30. The other leg 202 of bracket 201 projects from base 30 in the same direction as handle 11 and is positioned adjacent to the latter. Leg 202 is provided with elongated slot 202 to receive the shackle of a lock (not shown) to prevent unauthorized operation of handle 11 by blocking movement of the latter.

Occasionally, for safety reasons it is desirable to have devices of the type previously described constructed for operation -by a removable key instead of by the usual handle peviously described. Switch 10 may be readily converted for this type of operation by replacing operating handle 11 by stationary insulator 101 and movable Ueshaped insulator 104. The arms of insulator 104 embrace fixed pivot 31 and movable pivot 36 with the web of insulator 104 resting adjacent pivot 31. l

Insulator 101 is provided with slot 102 which receives the bifurcated end of key 103 to guide this end into U-shaped slot 112 in the periphery of insulator 104. 0peration of key 103 in the same manner as operation 10K (FIGURE 13) as was accomplished by handle 11 during the manual operation of switch 10.

Thus, it is seen that the instant invention provides a novel construction for a double pole switch which is exceptionally compact for a given horsepower rating. Assembly of the switch elements is very simple and it is a simple matter to change the heater for the overload trip device without disturbing the line and load wiring or removing the switch from the junction box. In this connection it is noted that only a single screw type connection is required for the replaceable heater and that such connection is sufficient to achieve reliable mechanism securernent of the heater.

Although there has been described a preferred ernbodiinent yof this novel invention, many variations and modifications will now be apparent to those skilled in the art. Therefore, this invention is to be limited, not by the specific disclosure herein, but only by the appending claims.

The embodiments of the invention in which an exclusive privilege or property is claimed are defined as follows:

1. An electric switch including `a releasable cradle, a fault responsive trip means normally maintaining said cradle in a reset position, a first actuator, a main spring connecting said first actuator to said cradle, a `second actuator, a movable pivot connecting saidV actuators to each other, contact means including a movable portion connected to said first actuator for operation thereby, a fixed pivot about which said second actuator is movable between a first and a second position; with said cradle in said reset position operation of said second actuator to said second position moves said movable pivot in a first direction over center with respect to said spring whereupon said spring is effective to open said contact means and operation of said second actuator to said first position moves said movable pivot in a second direction, opposite to said first direction, over center with respect to said spring whereupon said spring is effective to close said contact means; 4release of said cradle by said trip means permitting said spring to move past said movable pivot to open said contact means and to prevent said actuator from operating said contact means closed; a housing wherein said cradle, said trip means, said actuators, said contact means, and said main spring are disposed; said housing having an opening; additional means mounted to said housing for positioning a member extending through said -opening into operative engagement with said second actuator and guiding movement of such member for operation of said second actuator between said first and second position.

2. An electric switch as set forth in claim 1 also including a frame having spaced walls; `said housing including a base having an open side and a cover secured t-o said base and positioned over said side; said housing including additional walls between which said frame is positioned, said additional walls each having a groove extending to said side; said fixed pivot extending through said walls into said grooves.

3. An electric switch as set forth in claim 2 in which said additional means comprises a pin means extending through said walls into said grooves.

4. An electric switch as set forth in claim 1 in which said first and said second actuators are each generally U-shaped elements having spaced arms joined by a web; said arms of said first actuator positioned between the arms of said second actuator.

5. An electric lswitch as set forth in claim 4 in which said main spring is a coiled member under tension having one of its ends connected to the web of the first actuator and its other end connected to said cradle.

6. An electric switch as set forth in claim 5 in which there is an insulating carrier connecting said first actuator to `said contact means; said housing including formations guiding said carrier for movement in a plane; a second fixed pivot at one end of said candle; said trip means engageable with said cradle .at the other end; said other end of said spring connected to said cradle at a projecting portion intermediate the ends of said cradle; said projecting portion extending toward said open side when said cradle is in said reset position.

7. An electric switch as set forth in claim 6 in which the cradle is so positioned that a line extending between said ends of said cradle is generally perpendicular to said plane which said cradle is in said reset position,

8. An electric switch as set forth in claim 1 in which said trip means includes a first portion directly engageable with said cradle and a second portion for indirectly heating said first portion; a first plug-in connector part at one end of said second portion and a second plug-in connector part disposed in said housing to removably engage said first plug-in connector part; a conducting strap constructed of sheet material; said contact means including a stationary portion mounted on said strap; said second plug-in connector part formed of said sheet Inaterial integral with said strap.

9. An electric switch as set forth in claim 1 in which said trip means includes a first portion directly engageable with said cradle and a second portion for indirectly heating said first portion; a first plug-in connector part at one end of said second portion and a second plug-in connect-or part disposed in said housing to removably engage said first plug-in connector part; a terminal part at the other end of said second portion; a screw captively mounted to said terminal part; said screw having a head accessible for oper-ation external of said housing; a threaded formation carried by said housing and positioned to receive said screw; said screw when turned to withdraw ysame from said threaded formation acting to disengage said first plug-in -connector part from said `second plug-in connector part.

References Cited bythe Examiner UNITED STATES PATENTS 2,360,431 10/1944 Link 200-116 2,362,257 ll/ 1944 Favre 200--116 3,240,904 3/1966 Dowdle et al 200-116 BERNARD A. GILHEANY, Primary Examiner, H, B. GILSON,Ass1starttEyJ camner, 

1. AN ELECTRIC SWITCH INCLUDING A RELEASABLE CRADLE, A FAULT RESPONSIVE TRIP MEANS NORMALLY MAINTAINING SAID CRADLE IN A RESET POSITION, A FIRST ACTUATOR, A MAIN SPRING CONNECTING SAID FIRST ACTUATOR TO SAID CRADLE, A SECOND ACTUATOR, A MOVABLE PIVOT CONNECTING SAID ACTUATORS TO EACH OTHER, CONTACT MEANS INCLUDING A MOVABLE PORTION CONNECTED TO SAID FIRST ACTUATOR FOR OPERATION THEREBY, A FIXED PIVOT ABOUT WHICH SAID SECOND ACTUATOR IS MOVABLE BETWEEN A FIRST AND A SECOND POSITION; WITH SAID CRADLE IN SAID RESET POSITION OPERATION OF SAID SECOND ACTUATOR TO SAID SECOND POSITION MOVES SAID MOVABLE PIVOT IN A FIRST DIRECTION OVER CENTER WITH RESPECT TO SAID SPRING WHEREUPON SAID SPRING IS EFFECTIVE TO OPEN SAID CONTACT MEANS AND OPERATION OF SAID SECOND ACTUATOR TO SAID FIRST POSITION MOVES SAID MOVABLE PIVOT IN A SECOND DIRECTION, OPPOSITE TO SAID FIRST DIRECTION, OVER CENTER WITH RESPECT TO SAID SPRING WHEREUPON SAID SPRING IS EFFECTIVE TO CLOSE SAID CONTACT MEANS; RELEASE OF SAID CRADLE BY SAID TRIP MEANS PERMITTNG SAID SPRING TO MOVE PAST SAID MOVABLE PIVOT TO OPEN SAID CONTACT MEANS AND TO PREVENT SAID ACTUATOR FROM OPERATING SAID CONTACT MEANS CLOSED; A HOUSING WHEREIN SAID CRADLE, SAID TRIP MEANS, SAID ACTUATORS, SAID CONTACT MEANS, AND SAID MAIN SPRING ARE DISPOSED; SAID HOUSING HAVING AN OPENING; ADDITIONAL MEANS MOUNTED TO SAID HOUSING FOR POSITIONING A MEMBER EXTENDING THROUGH SAID OPENING INTO OPERATIVE ENGAGEMENT WITH SAID SECOND ACTUATOR AND GUIDING MOVEMENT OF SUCH MEMBER FOR OPERATION OF SAID SECOND ACTUATOR BETWEEN SAID FIRST AND SECOND POSITION. 